A British businessman on hunger strike in a Dubai prison where he is serving a 23-year sentence for allowing cheques to bounce is reported to have suffered a stroke.

Peter Margetts, a property developer from Kew, west London, was jailed after a series of post-dated cheques bounced when a waterfront venture failed in 2008 when the property market slumped. He is one of a score of foreigners jailed in Dubai for bouncing cheques who are said to be on hunger strike.

Radha Stirling, founder of the campaign group Detained in Dubai, said yesterday: "I have spoken to several of the prisoners who were on hunger strike with Peter. They have confirmed to me that Peter has suffered a stroke and is in a very bad way."

Last month, Mr Margetts said: "I've lost hope. I'm here for longer than some people get for murder, rape and really heinous crimes."

Bouncing cheques is against the law in Dubai as part of rules designed to protect investors. The laws are widely regarded as out of date.